PCB Test Jigs & My China Connection

When a test jig was returned, we discovered that the industrial computer we'd sent as part of the jig had been replaced with a beaten-up commercial-grade PC.

Every time I have seen (or written) a comment that is even vaguely critical of industry in China, there seems to be an avalanche of responses in its defence. Often, they fight fire with fire, and so I write this blog with some trepidation.

Let me say at the outset that all my experiences are based on the statistically insignificant sample of two. If you are dealing with companies like Foxconn, then I can't believe you would see any of what I am about to describe. Perhaps you won't even see it at much smaller companies -- but it did happen to us.

Apparently, it is very difficult to ship equipment into China, and it is really complicated to ship PCs even if they form part of some test equipment. Somehow we have managed to do it. In one case we had a test jig comprising a PC plus some electronics plus a bed of nails. Since the unit was based on obsolete PC ISA bus technology, and because we were planning on shipping it over long distances, we upgraded the system to an industrial computer (with a solid state disk) so that it certainly did not look like a PC.

This test jig was in use for several years, moving from one manufacturer to another. Eventually, the jig failed, so it was shipped it back to Canada. At the same time, we dispatched our duplicate jig to China. Imagine our surprise when the original jig arrived and we discovered that the PC was a beaten-up, non-functional, commercial-grade PC with a dead disk drive. No one knows when or where the substitution occurred.

In another case of test jig malfunction, I tried to perform some diagnostics over the phone. The conversation would go like this: I would ask the interpreter here in Toronto to ask the technician in China if a particular LED on a relay was on. This was communicated via a relatively lengthy conversation, which I presume was defining exactly which LED to look at. The conversation would then pause for about five minutes. The technician would then come back on the phone and there would be another conversation before I got the answer. This carried on for quite some time.

Eventually, I asked why there was always the long hang time before we received an answer. It turned out that the phone was about two minutes' walk away from the test jig -- the technician had to walk over, take a look, and then return! Based on this experience, we reappraised the intercontinental exchange of test jigs.

The production facilities that I have seen in China are not climate-controlled. Not only is the shop hot and humid in summer and cold in winter, there is dust as well. Due to this, our test jigs became grimy and even rusty. Some of the gold-plated relays failed well before their rated operational life in one of the failures described above. We were actually asked (after our complaints) if we wanted the test jigs to be stored in air-conditioned storerooms.

We have an ongoing problem with printed circuit boards (PCBs). We email the Gerber plots to our subcontractor, who farms them out to a board shop. For some reason, the board shop moves tracks around. There is no logic to the changes and I can think of no justifiable reason to do this without the customer's permission, but it is especially concerning when your products carry UL/CSA agency approvals. To counteract these spurious changes, once the Gerbers have been reproduced, they are transmitted back to us and we have to check by overlaying the original against the new. This is wasteful and prone to human error, so occasionally unwanted, unrequested, and unauthorized changes do sneak through.

Aubrey, you say: "and obviously the experience is profitable for us". This is the fuel that keeps things like those happening. So, I am affraid to say, somehow you (or your Company) deserve the pain and stress that all of this brings. So, with all respect, please enjoy!

@Antedeluvian: The conversation would go like this: I would ask the interpreter here in Toronto to ask the technician in China if a particular LED on a relay was on. This was communicated via a relatively lengthy conversation...

This reminds me of a television documentary I saw more than 20 years ago in the UK. There was an English reporter/investigator questioning a Japanese (or Taiwanese or Korean -- I forget) businessman -- they were standing in some industrial setting like a shipyard. All of the questions and answers went through a translator.

At one point the interviewer said something like "So, are the reports true that you've been syphoning off some of your company's money into your personal accounts?"

After that was translated, the businessman went into a 5-minute diatribe -- jumping up and down -- waving his arms around -- shouting -- bright red in the face -- the Full Monty. Eventually he ground to a halt .. the interpreter turned round to the reporter and said "No." LOL

>For some reason, the board shop moves tracks around. There is no logic to the changes and I can think of no justifiable reason to do this without the customer's permission, but it is especially concerning when your products carry UL/CSA agency approvals.

Sounds like you need a new board shop. That's what I once told our drafting department when I asked for controlled impedance traces and they told me the pcb vendor would just laugh at this request.

Heard a tale several years back about a board shop that would enlarge clearances around vias through ground planes, probably so their process could be cheaper. This cut the plane wide open and introduced slots and no-connects.

Why not visit vendor before you start your business. If you avoid doing your essential homework of vendor selection, you may get similar results.

Some manufacturers have their own permanent quality representative at their Chinese subcontractor(s). I guess there are some who send out someone with every contract. We are too small and/or the profits aren't significant enough to allow for these costs. We deal with one manufacturing house. Every time we place an order, they review the components and their subcontractors (as they should) and give us a quote based on those numbers. We have no way of knowing what the quality of their subcontractors will be. We simply reuire that the end product meets our standards.

But if it fails to meet those standards- irrespective who gets the blame, it looks bad on us because there would be late deliveries.